I just (a few minutes ago) put an AutoZone H7-AGM in my 2008 E90. Don't know if your car is the same. The AutoZone H7 fit like a glove. I just had to reverse which end of the battery had the plug in the vent line hole. Thanks to GeneralXception for the excellent DIY.

The AutoZone website says H8 or group 49, but the one that came out of the car is a H7 form factor. I think the H8 might fit but it would be really tough to get it in there. Which battery you have might depend on how many extras are on your car (e.g. winter package). There are a series of holes in the floor of the battery box that allow other length batteries to be used, including one that probably would work for the longer H8. However, my car did not have the hold down with the long bolt on it as shown in the DIY, so I had to reach down in there to pull it out. That would have been tough to impossible to replace with an H8 battery.

To the guys who didnt register after battery change have you had any issues?

Reading through the thread I see a year or so has passed for some who have changed battery and not registered.

I'm wondering if if not registering can effect an E90 with start/stop function but can't help but come back to the thought that the "registering" is a scam.

I can't see it being truly a scam... Over engineered and not always required... Sure.. Scam... Not so much. Really the registration only takes a few minutes, it's not a big deal. BMW recommends it, I can't see a reason not to do it.

I'd like to provide my input as I think it may help some of you. I came to this forum because my 2006 E90 330i (manual transmission) was not turning over as well as it once was and I thought the battery was beginning to go. One day a couple of weeks ago (as it is getting colder) I noticed that the rear defogger/de-icer was not working. I also was encountering problems with the HVAC fan speed. I lost the fastest three speeds and it also began to sporadically change speeds, especially when I was slowing for a stop sign or red light. Trying to gain information to help me address it, I began at the beginning of these posts an was trying to decide whether I should replace the battery myself and gamble on the registration or if I should suck it up, go to the dealer, cough up the dough, and hope the battery would solve the other two issues, thus being money (very) well spent. Then I read post #118. After that, I decided to go to the local dealership and have them install and register a new battery. It cost about $350. While waiting for it this past Saturday morning, I sat in a comfortable waiting area and next to the show room with the new Lime Rock Edition M3 and the new M5, among other awesome cars. After a couple of hours, I paid and left. When I got in the car the first thing I checked was the HVAC blower. It worked perfectly. I cannot say that I have tried the rear defogger yet because I haven't needed to but I am confident it will work fine. When you think about trying to save maybe $200 to do this one yourself and then you think about the cost of all the other maintenance, let alone tires, for this car, I personally conclude it was money very well spent. To me spending money on maintenance feels much better than spending money on repairs.

I went to my stealership last night to get a quote for battery replacement on my 2006 330i (2005 manufacture date). It has the old lead acid battery, not the AGM battery. The service technician came out and told me that even though they will register the battery if they do it, he doesn't think there would be a problem if it wasn't registered as it's a lead acid type battery. The AGM batteries need to be registered as they are much more sensitive. Anyways, I ended up just buying the OEM battery from them, $176+tax. they would have charged me $376+tax for them to do the whole thing.

I also asked them if there was any point to upgrading to an AGM battery for better performance/cold cranking ability. He said, not really a big difference and not worth it since if you upgrade to AGM from lead acid, then you'll have to register the battery.

Posted to this thread some time ago. I wanted to provide an update that the replacement OEM battery (same specs as factory battery) that I installed in June 2010 is still starting without issue. The registration process was skipped per the advice of the shop foreman at my local BMW Center.

What model and part number is your replacement battery? I have the same car as you I think. I will need to buy one sometime soon. Thanks

Hi from cold and frosty UK. I need to replace battery on my BMW 3 series tourer 325ia SE 2007 (February). These illustrated instructions will prove very helpful. I want to install a 90amp bettery instead of a 70amp which was the original. Opinions seem to differ massively about whether one needs to reprogramme the car to tell it you have anstalled a new battery. On balance I guess it will be safer to assume that you should. My local BMW Dealer ( Mr Ripoff) will not install a battery I would bring him but will only install a battery I but from the dealership at about twice the price plus about $150 (£84) labour. I have purchased from EBay the diagnostic lead plus the software DVDs. Has anyone done this procedure and if so can they run me through it step by step please. Thanks in advance and very glad to have joined as a new member. I live at Bexleyheath which is in Kent, SE England about 15 miles from London. Regards to you all.

Last weekend I bought an Everstart Maxx H8 battery from Walmart. It was ~$128 out the door with a 3 year warranty. I emailed the manufacturer, Johnson Controls, and they stated it's 80AH, 150RC. Similar to what's already in the car (90AH/160RC). CCA is a bit higher than the original (760 comapred to 720).

Because of the change, I'm going to get it registered/coded. Let me know how it goes.

I just inherited a 2006 BMW 325i sedan from my sister a couple of weeks ago, she told me she had had trouble with the battery dying on her a couple of times before giving the car to me and over the course of the last 2 weeks I have been having more and more difficulty starting the car. I came across this thread and it seems that by in large the folks who have posted that they did not need to register their new battery and everything was fine either got a replacement OEM battery from the BMW dealer, or an OEM spec battery from the auto store, which would make perfect sense seeing as how the computer would still be telling the alternator to charge the battery properly. But any battery that has different spec ratings from the original would seem to need to be re-registered to work properly. I called around to various independent shops in my area and two of them said they have never heard of the adaptation reset, one said that it definitely needed to be done (yet ironically was cheaper than the others--$55), and another said it definitely did NOT need to be done but told me if I really wanted it done they would do it for me free of charge. Makes me really wonder if I should trust my car to a supposed expert BMW authorized repair shop that didn't even know this needed to be done on a different-spec replacement battery.

I just inherited a 2006 BMW 325i sedan from my sister a couple of weeks ago, she told me she had had trouble with the battery dying on her a couple of times before giving the car to me and over the course of the last 2 weeks I have been having more and more difficulty starting the car. I came across this thread and it seems that by in large the folks who have posted that they did not need to register their new battery and everything was fine either got a replacement OEM battery from the BMW dealer, or an OEM spec battery from the auto store, which would make perfect sense seeing as how the computer would still be telling the alternator to charge the battery properly. But any battery that has different spec ratings from the original would seem to need to be re-registered to work properly. I called around to various independent shops in my area and two of them said they have never heard of the adaptation reset, one said that it definitely needed to be done (yet ironically was cheaper than the others--$55), and another said it definitely did NOT need to be done but told me if I really wanted it done they would do it for me free of charge. Makes me really wonder if I should trust my car to a supposed expert BMW authorized repair shop that didn't even know this needed to be done on a different-spec replacement battery.

I did the same thing by calling around and this is what I found, shops that never heard if the registering said don't need it, while those that did said that they would not do it and would recommend BMW do it. So would you rally trust a shop that has no idea of what you are talking about to put a battery in your car so they can make some money off of you? The shops that did say they wouldn't touch it simply didn't want me to come back to them for any trouble as only BMW can reset / register. I paid the dealer to do it, two year warrantee and now all of my electronics work fine as was having issues with rear defogger and blower.

I did the same thing by calling around and this is what I found, shops that never heard if the registering said don't need it, while those that did said that they would not do it and would recommend BMW do it. So would you rally trust a shop that has no idea of what you are talking about to put a battery in your car so they can make some money off of you? The shops that did say they wouldn't touch it simply didn't want me to come back to them for any trouble as only BMW can reset / register. I paid the dealer to do it, two year warrantee and now all of my electronics work fine as was having issues with rear defogger and blower.

No, I would not trust the shops I called that had no idea what I was talking about to a) install my battery for me (I can do that myself as did most everyone else on here,) b) register the battery since they wanted to charge me over $100 to do something they never heard of.
Now, would I trust the guy who actually DID know exactly what I was talking about and only wanted $55 for the labor? Of course, why not? As has been made clear in this thread all it takes is the scan tool.
Would I trust the guy who said he knew what I was talking about but said it didn't need to be done, but would charge me a big fat $0 vs approx $200 at the dealer if I wanted it done anyway? Well, that one's kind of a toss up, but I find it kind of hard to not get it done by someone who knows what the procedure is and is willing to do it for free, even if he doesn't believe in it.

It's me again from a very cold UK. Have not yet replaced the battery but have purchased a BMW diagnostic lead and the software, which seems massively complicated. Also the BMW Technical Information System (workshop manual). This is ambivalent as it says that the car "might" need reprogramming depending on what original equipment it had when manufactured, referring to an automated battery charging system. Which means I gues that you risk frying battery or not charging it enough if you do not register a new battery. The battery now specified for my car, 325iaSE Tourer, is 90 amp/hrs whereas the original one installed is 70 amp/hrs, so for safeties sake I want to register it to the car's computer system. I am now seeking an old but working laptop to install the diagnostic software on to, but this near Christmas will just keep charging the old battery with a mains charger. I do not have a laptop and my wife will not let me have hers in case I blow it up, as the software is obviously cloned! Bryan King

Great post. Many thanks to the original poster for providing all the great pics and thanks to everyone else for your comments. For what it's worth...I registered my new battery Wal-mart H6 with the BT Tool (enthusiast version). Cleared codes, re-scanned and everything looks great. Thanks again.

My 06 330i killed the autozone replacement in 2 months. I have the bav tech on the way to do the register. Not too big of a deal considering it has a warranty and was replaced free of charge but I guess Im proof that the registration is or may be ness.

Last weekend I bought an Everstart Maxx H8 battery from Walmart. It was ~$128 out the door with a 3 year warranty. I emailed the manufacturer, Johnson Controls, and they stated it's 80AH, 150RC. Similar to what's already in the car (90AH/160RC). CCA is a bit higher than the original (760 comapred to 720).

Because of the change, I'm going to get it registered/coded. Let me know how it goes.

Got the same one, just replaced it today. Fits perfectly, same size, more powerful, cheaper & has vent hole at the same spot.